refactor(javascript): own source range validation once

src/domain/javascript/javascriptSourceCoordinates.ts

@@ -0,0 +1,22 @@
+import { z } from "zod";
+
+const sourcePointSchema = z.strictObject({
+  line: z.number().int().min(1),
+  column: z.number().int().min(0),
+});
+
+/** JavaScript source coordinates use one-based lines and zero-based columns. */
+export const javascriptSourceRangeSchema = z
+  .strictObject({ start: sourcePointSchema, end: sourcePointSchema })
+  .superRefine((range, context) => {
+    if (
+      range.end.line < range.start.line ||
+      (range.end.line === range.start.line &&
+        range.end.column < range.start.column)
+    )
+      context.addIssue({
+        code: "custom",
+        path: ["end"],
+        message: "Source range end must not precede its start",
+      });
+  });